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We report on the development of the first-ever inorganic radiation-hard moisture-insensitive large volume spectroscopic semiconductor-based scintillator with less than 2 ns decay time and light yields as high as 8000 ph/MeV. Despite extensive research into scintillator materials, the quest for an ideal scintillator combining ultrafast decay times (akin to BaF2 and Yb-doped scintillators such as Lu2O3:Yb), high light yields (exceeding 2000 photons per MeV), spectroscopic capabilities, and exceptional radiation hardness remain unfulfilled. In this study, we demonstrate and report for the first time the viability of large-volume (up to 20 mm thickness) gallium oxide (β-Ga2O3) semiconductor-based scintillators for applications requiring these properties. These β-Ga2O3 scintillators were grown using the fast turnaround (∼2 days) crucible-free optical float zone (FZ) technique. The high light yield and ultrafast decay time of these high-purity n-type semiconductors with free carrier concentration of 6 × 1017 cm−3 are attributed to native defects, specifically oxygen vacancies (VO) and gallium–oxygen vacancy pairs (VGa–VO), generated during optimized FZ growth. The ultrafast decay, along with high light yield, enables excellent timing resolution and high count rate detection for applications like time-of-flight positron emission tomography, physics experiments, and nuclear safety. The radiation hardness of these devices has been documented in a separate publication. [ABSTRACT FROM AUTHOR]

The monoclinic (In 0.25 Al 0.75) 2 O 3 alloy has been suggested as an ideal material to create monoclinic Ga 2 O 3 heterostructures, as it provides a close lattice match to β - Ga 2 O 3 along with a 1 eV conduction-band offset. Achieving intentional n -type doping in Ga 2 O 3 heterostructures is important for device applications, but this may be difficult due to the high Al content of this alloy. Here, we use density functional theory with a hybrid functional to investigate common donor dopants, in particular, Si, Sn, C, and Ge substituting on cation sites, and H interstitials, in In 2 O 3 and InAlO 3. We identify Si as the optimal donor, as it is a shallow donor for In concentrations above 14%. Its formation energy is also low, indicating that these donors will incorporate during growth. For higher In concentrations, Sn (above 33% In) and Ge (above 35% In) are also promising donors, with Sn having comparable formation energies to Si. [ABSTRACT FROM AUTHOR]

4H Silicon carbide (SiC) is widely recognized as one of the most advanced wide bandgap semiconductors used in the production of high-efficiency power electronic devices. Impurities play a crucial role in achieving the desired electrical properties in 4H-SiC, yet the understanding of impurities in this material remains limited. In this study, first-principles formation-energy calculations were employed to establish a comprehensive database of formation-energy diagrams for impurities in 4H-SiC. This database includes valuable information on site preference, lattice distortion, solubility, and charge transition levels (CTLs) of the impurities. The site preference for each impurity is closely related to factors such as the Fermi energy, chemical potential, and the impurity species itself. To assess the lattice distortion caused by each impurity, a comparison was made between the volume changes before and after doping. Moreover, the solubility of each impurity was determined using the detailed balance theory, thereby enabling a direct measure of the maximum impurity concentration achievable in the material. Based on the CTLs, the impurities in 4H-SiC were classified into four categories: n-type impurities, p-type impurities, amphoteric impurities, and non-electroactive impurities. This comprehensive property database for impurities in 4H-SiC provides valuable insights for tailoring the material properties through controlled doping, thereby ultimately leading to enhanced performance of power electronic devices. [ABSTRACT FROM AUTHOR]

The effect of high temperature annealing under O2 and N2 atmospheres on the electrical properties and defect formation on Sn doped n-type β-Ga2O3 bulk samples was investigated by electron paramagnetic resonance (EPR) spectroscopy. EPR, being a volume sensitive technique, probes the entire sample volume. Our results show an electrical compensation being correlated with the formation of a negatively charged Ga vacancy defect VGa2−. This VGa center is different from the one observed after particle irradiation. The associated shift of the Fermi level reveals the presence of Fe3+, Cu2+, and Cr3+, which are residuals related to the growth conditions. The 1100 °C N2 annealed sample is fully compensated, and the neutral donor resonance is no longer observed. Our results directly confirm the thermal instability of Ga and Sn in n-type conducting samples. No oxygen vacancy related centers were detected. We discuss the various Ga vacancy centers reported previously. [ABSTRACT FROM AUTHOR]

Achieving high electrical conductivity (σ) and power factor (PF) simultaneously remains a significant challenge for n‐type organic themoelectrics (OTEs). Herein, we demonstrate the state‐of‐the‐art OTEs performance through blending a fused bithiophene imide dimer‐based polymer f‐BTI2g‐SVSCN and its selenophene‐substituted analogue f‐BSeI2g‐SVSCN with a julolidine‐functionalized benzimidazoline n‐dopant JLBI, vis‐à‐vis when blended with commercially available n‐dopants TAM and N‐DMBI. The advantages of introducing a more lipophilic julolidine group into the dopant structure of JLBI are evidenced by the enhanced OTEs performance that JLBI‐doped films show when compared to those doped with N‐DMBI or TAM. In fact, thanks to the enhanced intermolecular interactions and the lower‐lying LUMO level enabled by the increase of selenophene content in polymer backbone, JLBI‐doped films of f‐BSeI2g‐SVSCN exhibit a unprecedent σ of 206 S cm−1 and a PF of 114 μW m−1 K−2. Interestingly, σ can be further enhanced up to 326 S cm−1 by using TAM dopant as a consequence of its favorable diffusion behavior into densely packed crystalline domains. These values are the highest to date for solution‐processed molecularly n‐doped polymers, demonstrating the effectiveness of the polymer‐dopant matching approach carried out in this work. [ABSTRACT FROM AUTHOR]

The improvement of the water oxidation capability of bismuth molybdate (BM) with selective metal addition under illumination was examined. BM and its Zn-modified (different atomic %) photoanodes were developed over conducting glass substrate through the cost-effective drop-cast method. The maximum photocurrent of ~ 240 µA/cm2 at an applied potential of 1.3 V vs Ag/AgCl was recorded for the 2% Zn modified sample in 0.1 M Na2SO4 solution (PBS, pH 7) under 100 mW/cm2 illuminations. Surface characterizations like scanning electron microscopy, X-ray diffraction, energy dispersive X-ray analysis, and optical analysis such as UV–vis absorbance, photoluminescence, FT-IR, and Raman spectroscopic analyses were performed to determine the physicochemical properties of the semiconductor. The pure bismuth molybdate shows an optical band gap of ~ 2.78 eV, which decreases for the Zn-modified sample, and a minimum of 2.55 eV is detected for the optimized sample. The XRD analysis also reveals that Zn addition into the bismuth molybdate matrix decreases crystallite size with variation in proportions of the constituent metal oxides. The stability of the semiconductors regarding the PEC water oxidation reaction indicates promising results even under continuous illumination for 1 h. The Mott-Schottky study reveals the n-type nature of the semiconductors, whereas the Nyquist analysis indicates minimum charge transfer resistance for the 2% Zn-BMO sample. The PEC action spectra for the optimized photoanode indicate a maximum of 34% incident photon to current conversion efficiency with corresponding 38% absorbed photon to current conversion efficiency, which is more than three times than that of the pure bismuth molybdate. [ABSTRACT FROM AUTHOR]

The potential use of n-type small organic molecules in electrodes has attracted significant attention in organic electronics owing to the easy, high-yield purification processes of organic compounds. However, only few studies have reported high-efficiency supercapacitors based on n-type organic materials. Nevertheless, most n-type organic compounds possess low capacitance and poor cycling efficiency. Therefore, it is crucial to develop n-type organic compounds that demonstrate good electrochemical properties for use in electrodes. Herein, both the (E)-N-(4-(diphenylamino)benzylidene)-6,6,10,10-tetramethyl-4-phenyl-6,7,8,9,10,10a-hexahydro-5H-6a,9-methanobenzo[H]quinazolin-2-amine (TPAB) and (E)-N-(4-(diphenylamino)benzylidene)-4-(4-(diphenylamino)phenyl)-6,6,10,10-tetramethyl-6,7,8,9,10,10a-hexahydro-5H-6a,9-methanobenzo [h]quinazolin-2-amine (TPANB) compounds containing electrochromic (EC) and aggregation-induced emission (AIE) groups were synthesized from triphenylamine (TPA) and quinazoline derivatives, and their structure and properties were investigated. These novel electrode materials demonstrate high EC and fluorescence performance just as a typical n-type semiconductor. The coloring time of a TPANB film is 4.00 s, whereas the bleaching time is 3.00 s. Compared with TPANB, TPAB electrode material demonstrate a high area-specific capacitance (2.38 mF cm−2 at 0.05 mA cm−2), outstanding the charge and discharge rate performance (93% with the current density of 0.05–0.25 mA cm−2), and excellent cycling performance (78.51%) after 300 cycles. Above all, the multifunctional materials hold good potential for intelligent display energy storage. [ABSTRACT FROM AUTHOR]

Based on the hybrid functional method, the electronic structure, optical property and electron effective mass of α -Ga2O3, together with the properties for intrinsic and extrinsic defects incorporated into α -Ga2O3 are studied. Obtained results indicate the α -Ga2O3 possesses a wide band gap (5.31 eV), small electron effective mass (0.22 m0) and a high visible light transmittance. The nonstoichiometric α -Ga2O3 is not an excellent n-type semiconductor. To improve the n-type conductivity, the W-doped α -Ga2O3 is studied. We find that W Ga is a promising n-type defect due to its relatively small ionization energy ϵ (0/+) (0.30 eV). When the equilibrium fabrication method is selected, the WO2 is a promising dopant source. Using the equilibrium fabrication method, the defect complex (V O+ W Ga) would be formed, and the ionization energy ϵ (0/+) for defect complex (V O + W Ga) would decrease to 0.08 eV, which implies that a great number of free electrons could be induced in the samples. We expect that this work can promote the understanding of the n-type conductivity for α -Ga2O3 and provide significant insights for the development of a transparent n-type semiconductor. [ABSTRACT FROM AUTHOR]

The twisted conformer of bistricyclic aromatic enes (BAEs) has a small HOMO–LUMO gap owing to the twisted double bond. In this study, we synthesized diphenoquinones fused with thiophene rings as a new twisted conformer-predominant BAE. They exhibited deep LUMO energy levels and apparent n-type semiconductor properties. [ABSTRACT FROM AUTHOR]

Developing novel n‐type organic semiconductors is an on‐going research endeavour, given their pivotal roles in organic electronics and their relative scarcity compared to p‐type counterparts. In this study, a new strategy was employed to synthesize n‐type organic semiconductors featuring a fully fused conjugated backbone. By attaching two sets of adjacent amino and formyl groups to the indacenodithiophene‐based central cores and triggering a tandem reaction sequence of a Knoevenagel condensation‐intramolecular cyclization, DFA1 and DFA2 were realized. The solution‐processed organic field effect transistors based on DFA1 exhibited unipolar n‐type transport character with a decent electron mobility of ca. 0.10 cm2 V−1 s−1 (ca. 0.038 cm2 V−1 s−1 for DFA2 based devices). When employing DFA1 as a third component in organic solar cells, a high power conversion efficiency of 19.2 % can be achieved in ternary devices fabricated with PM6 : L8‐BO : DFA1. This work provides a new pathway in the molecular engineering of n‐type organic semiconductors, propelling relevant research forward. [ABSTRACT FROM AUTHOR]

For selective detection of hydrogen, temperature modulation of a metal oxide sensor was used — heating for 2 s to 723 K and cooling for 13 s to 373 K. A gas-sensitive material based on tin dioxide with additions of palladium (3 wt. %) and platinum (0.5 wt. %) was prepared by the sol–gel method from nanopowder. The combination of temperature modulation with a specially selected composition of the gas-sensitive layer of the sensor made it possible to detect anomalous maxima in the sensor resistance curves versus time/temperature when determining hydrogen and its mixture with methane. It is shown that the most likely reason for the appearance of these maxima is the appearance of proton conductivity in addition to the usual electronic conductivity for an n-type semiconductor. The possibility of determining the composition of a hydrogen-methane mixture using a single metal oxide sensor with temperature modulation has been demonstrated. To determine the composition of the mixture, two methods of processing multivariate data were used. The first method is relatively complex and is based on principal component analysis. The second method is simpler for practical implementation and uses the coordinate of an additional maximum in the sensor resistance curves versus time/temperature. [Display omitted] • Analysis of H 2 +CH 4 mixture with air using temperature modulation of a single sensor. • Anomalous response to hydrogen, probably due to increased proton-type conductivity. • Qualitative and quantitative analysis of gas mixtures using PCA and maximum points. [ABSTRACT FROM AUTHOR]

In the case of low-dimensional semiconductor devices, the basic physical properties of materials can be measured through device manufacturing using single crystal synthesis and exfoliation, but for expansion into various application fields, technology that can synthesize the material itself directly on the substrate is needed. For multi-composition low-dimensional semiconductor materials like Nb2Pd3Se8, the physical characteristics of constituent elements differ, making direct growth control on a substrate extremely challenging. This study successfully synthesized Nb2Pd3Se8 wires using different metal precursors (niobium and palladium) through liquid precursor–intermediated chemical vapor deposition (LPI-CVD). By adjusting the concentration of the liquid precursor and the synthesis temperature, the reproducible growth of Nb2Pd3Se8 wires was achieved, ranging in lengths from 2.29 to 15.04 μm. It was confirmed that PdSe2 is initially synthesized at lower temperatures (below 620 °C), and at temperatures above 620 °C, this PdSe2 transforms into Pd17Se15. Nb2Pd3Se8 is synthesized from the Pd17Se15 at these higher temperatures. X-ray diffraction (XRD) analysis revealed that the wires exhibit a preferred orientation along the (210) plane. Electronic device fabrication using these wires demonstrated their application potential as n-type semiconductors. Field-effect transistor (FET) measurements revealed remarkable performance, with an Ion/Ioff ratio of 575 and an electron mobility of 2.03 cm2 V−1 s−1. LPI-CVD provides a promising strategy for synthesizing ternary chalcogenide materials, opening possibilities for exploring diverse ternary phases. This study highlights the importance of controllability, reproducibility, and FET performance in growing Nb2Pd3Se8 wires via the CVD system, thereby paving the way for integrated applications and facilitating mixed-dimensional studies with other nanomaterials. [ABSTRACT FROM AUTHOR]

In the case of low-dimensional semiconductor devices, the basic physical properties of materials can be measured through device manufacturing using single crystal synthesis and exfoliation, but for expansion into various application fields, technology that can synthesize the material itself directly on the substrate is needed. For multi-composition low-dimensional semiconductor materials like Nb2Pd3Se8, the physical characteristics of constituent elements differ, making direct growth control on a substrate extremely challenging. This study successfully synthesized Nb2Pd3Se8 wires using different metal precursors (niobium and palladium) through liquid precursor–intermediated chemical vapor deposition (LPI-CVD). By adjusting the concentration of the liquid precursor and the synthesis temperature, the reproducible growth of Nb2Pd3Se8 wires was achieved, ranging in lengths from 2.29 to 15.04 μm. It was confirmed that PdSe2 is initially synthesized at lower temperatures (below 620 °C), and at temperatures above 620 °C, this PdSe2 transforms into Pd17Se15. Nb2Pd3Se8 is synthesized from the Pd17Se15 at these higher temperatures. X-ray diffraction (XRD) analysis revealed that the wires exhibit a preferred orientation along the (210) plane. Electronic device fabrication using these wires demonstrated their application potential as n-type semiconductors. Field-effect transistor (FET) measurements revealed remarkable performance, with an Ion/Ioff ratio of 575 and an electron mobility of 2.03 cm2 V−1 s−1. LPI-CVD provides a promising strategy for synthesizing ternary chalcogenide materials, opening possibilities for exploring diverse ternary phases. This study highlights the importance of controllability, reproducibility, and FET performance in growing Nb2Pd3Se8 wires via the CVD system, thereby paving the way for integrated applications and facilitating mixed-dimensional studies with other nanomaterials. [ABSTRACT FROM AUTHOR]

This study focuses on how the chemical makeup of the glass' basic components affects the glass' structure and optical characteristics. Four glass samples have been created for this purpose using the chemical formula; 94 mol% Na2B4O7—(6-x) mol% CeO2 – x mol% Ce(NO3)3, where 0 ≤ x ≤ 6. The Ce cations in this formula have two separate chemical sources, CeO2 and Ce(NO3)3, with CeO2 eventually being replaced by Ce(NO3)3. The standard melt-quenching technique was used to prepare the studied glasses. While X-ray direction (XRD), differential scanning calorimetry (DSC), and UV–vis were used for the structural and optical characterizations. XRD patterns revealed the short-range order glass networks for the prepared samples, while DSC thermograms showed that when CeO2 was replaced with Ce(NO3)3, the glass transition temperature (Tg) decreased, causing the glass stability to improve. The optical characterization resulted in the finding that when CeO2 was replaced with Ce(NO3)3, the Urbach's energy increased with a decrease in bandgap energies, which reflects an increase in the glass homogeneity. Finally, the results may imply that Ce(NO3)3-based glasses can be proposed for usage in applications for UV blockers, radiation shielding, light attenuation, and n-type semiconductors. [ABSTRACT FROM AUTHOR]

Electrical and thermal transport measurements on quenched NaCl-type Ag1/3Pb1/3Sb1/3Se reveal an n-type semiconductor with a Seebeck coefficient up to −140 μVK−1 and a thermal conductivity as low as 0.52 WmK−1. Short-range order is indicated by disorder diffuse scattering in electron diffraction patterns. In contrast, 4L-Ag0.61Pb1.79Sb2.61Se6 (space group Cmcm with a = 4.2129(1) Å, b = 13.852(1) Å, and c = 20.866(1) Å, Z = 4) features the first lillianite-type structure in the system Ag/Pb/Sb/Se. It consists of slab-like NaCl-type building blocks that are interconnected via trigonal [PbSe6] prisms. As such structures typically do not form with Te as an anion, the first "sulfosalt-like" compound, Ag0.38Pb0.25Sb2.38Te4, in the system Ag/Pb/Sb/Te forms a layered tetradymite-like structure (space group R 3 - m with a = 4.2887(1) Å, c = 41.544(1) Å, Z = 3). Its slabs, which are separated by van der Waals gaps, are built up from three layers of distorted [MTe6] octahedra. Crystals of Ag0.38Pb0.25Sb2.38Te4 were grown by chemical transport. [ABSTRACT FROM AUTHOR]

Based on the first principle, the change of photoelectric properties of non-metal-doped CrS2 under biaxial tension was studied. The formation energy indicates that the doping system is stable. Studies have shown that the partial doping system achieves a semiconductor metal phase transition. The strain opens the bandgap of the F-doped system, and the system changes from metal to n-type semiconductor. The Te-doped system realizes the transition from indirect bandgap to direct bandgap under the adjustment of 2% strain. The O and Se doping systems realize the reverse regulation of the bandgap under strain, and the conductivity gradually increases with the increase of strain. The absorption efficiency of Te doping under a certain strain is significantly enhanced, the static dielectric properties of the F doping system are increased by more than two times, the absorption spectrum response range is increased, and the absorption capacity of the system is enhanced. This lays a foundation for applying monolayer CrS2 in microelectronics and optoelectronics. [ABSTRACT FROM AUTHOR]

In this study, magnetically recyclable spherical Fe3O4/Cu2O particles comprising S-scheme heterojunctions were prepared by a simple hydrothermal approach using n-type semiconductor Fe3O4 as precursor and p-type semiconductor Cu2O. A Fenton-like system was thus constructed via the addition to Fe3O4/Cu2O of hydrogen peroxide. A rhodamine B (RhB) solution was used to simulate polluted wastewater, and photocatalytic RhB removal experiments were conducted under visible light irradiation. Powder X-ray diffractometry, vibrating-sample magnetometry, nitrogen adsorption–desorption, transmission electron microscopy, and X-ray photoelectron spectroscopy experiments were conducted to characterise Fe3O4 and Fe3O4/Cu2O composite. The band gap of Fe3O4/Cu2O was 1.76 eV, narrower than that of Fe3O4 (2.14 eV). The effects of the pH, sample dosage, hydrogen peroxide concentration, and RhB initial concentration on RhB removal were investigated. According to evidence, under the optimum reaction conditions, the RhB removal rate was 99.4%. The Fe3O4/Cu2O composite exhibited good photocatalytic efficacy even after four cycles of testing. Based on the results of free radical capture experiments, hydroxyl radicals and holes cooperated as main reactive species in the photocatalytic system. The Fe3O4/Cu2O photocatalyst can be easily removed based on magnetism, and it has been proven to be very effective for the degradation of RhB under both UV and visible light irradiation. [ABSTRACT FROM AUTHOR]

In recent years, Czochralski silicon (Cz-Si) crystals have been progressing toward n-type, large diameter and low oxygen concentration. For this purpose, the modified heating zone structure for 300 mm diameter n-type Cz-Si crystal growth with dual side-heaters has been proposed; moreover, its feasibility and effectiveness were verified through numerical simulations and on-site experiments herein. The simulation results indicate that the proposed crystal growth technique with modified parameters can effectively enhance the uniformity of longitudinal temperature gradient in the silicon melt and lower the temperature at the silica crucible bottom, for reducing the oxygen concentration at the crystal head. Based on it, 300 mm diameter n-type recharged Cz-Si (RCz-Si) crystals with an oxygen concentration in the range of 9.5–10.5 ppma were grown in on-site experiments, which is much lower than that grown in a conventional heating zone structure. More importantly, the photoluminescence (PL) images of the quarter wafers taken at the as-grown Cz-Si crystal head, middle and bottom have shown that little metastable defects can be annealed out during typical high-temperature oxidation at 1000 °C, confirming the excellent stability of thermally induced degradation. Consequently, this manuscript has demonstrated that the proposed crystal growth technique can realize dual goals of oxygen concentration control and crystal quality assurance in 300 mm diameter n-type Cz-Si crystal growth, which may promote the development of large diameter Cz-Si crystal growth techniques and the related application industries. [ABSTRACT FROM AUTHOR]

The n-type semiconductor SnO2 with a wide band gap (3.6 eV) is massively used in gas-sensitive materials, but pure SnO2 still suffers from a high operating temperature, low response, and tardy responding speed. To solve these problems, we prepared small-sized pure SnO2 using hydrothermal and freeze-drying methods (SnO2-FD) and compared it with SnO2 prepared using a normal drying method (SnO2-AD). The sensor of SnO2-FD had an ultra-high sensitivity to NO2 at 100 °C with excellent selectivity and humidity stability. The outstanding gas sensing properties are attributed to the modulation of energy band structure and the increased carrier concentration, making it more accessible for electron exchange with NO2. The excellent gas sensing properties of SnO2-FD indicate its tremendous potential as a NO2 sensor. [ABSTRACT FROM AUTHOR]

BiVO4 is an important n-type semiconductor used in photocatalysis due to its high capacity to absorb solar light in the 400–700 nm range, abundance, high chemical stability, non-toxicity, and low cost. However, research on physicochemical modifications to increase its catalytic activity via simple procedures is limited. In this work, the influence of different synthesis parameters, such as calcination temperatures or silver doping, on the structural and physicochemical characteristic of the BiVO4-based photocatalysts and their photocatalytic performance in degrading sulfamethoxazole from aqueous solution under blue-LED irradiation was evaluated. BiVO4-based photocatalysts were synthesized using a solvothermal method. The monoclinic phase (m-s) was successfully kept stable even after the thermal treatments at 300, 450, and 600 °C and the corresponding silver doping. The low bandgap of 2.40 eV and the average particle size of 18 nm of the BiVO4 catalyst treated at 300 °C seems to be the key. Afte doping, Ag/BiVO4 photocatalyst treated at the optimal found calcination temperature (300 °C) showed the best photocatalytic behavior. [ABSTRACT FROM AUTHOR]

In this paper, synthetically scaled-up degenerately n-type doped indium tin oxide (Sn:In2O3) nanocrystals are described as highly transparent conductive materials possessing both optoelectronic and crystalline properties. With tin dopants serving as n-type semiconductor materials, they can generate free-electron carriers. These free electrons, vibrating in resonance with infrared radiation, induce strong localized surface plasmon resonance (LSPR), resulting in efficient infrared absorption. To commercialize products featuring Sn:In2O3 with localized surface plasmon resonance, a scaled-up synthetic process is essential. To reduce the cost of raw materials during synthesis, we aim to proceed with synthesis in a large reactor using industrial raw materials. Sn:In2O3 can be formulated into ink dispersed in solvents. Infrared-absorbing ink formulations can capitalize on their infrared absorption properties to render opaque in the infrared spectrum while remaining transparent in the visible light spectrum. The ink can serve as a security ink material visible only through infrared cameras and as a paint absorbing infrared light. We verified the transparency and infrared absorption properties of the ink produced in this study, demonstrating consistent characteristics in scaled-up synthesis. Due to potential applications requiring infrared absorption properties, it holds significant promise as a robust platform material in various fields. [ABSTRACT FROM AUTHOR]

Phase-pure crystalline cubic boron nitride (c-BN) thin films are of immense scientific and technical interest because of their suitable properties for optoelectronic and high-power applications, high thermal conductivity and hardness, chemical inertness to ferrous materials in high-temperature and caustic environments, and high optical transmittance over a broad wavelength range from the ultraviolet (UV) to the visible spectrum. However, the lack of controlled fabrication techniques for high-quality c-BN films significantly affects the reliable practical applications of this material. Recently, phase-pure single-crystal c-BN and a new phase of BN with unique properties, called quenched-BN (Q-BN), have been synthesized using a pulsed laser annealing (PLA) technique to overcome the current impediments in c-BN synthesis. This review paper comprehensively examines the current status of analytical research on the growth, characterization, and properties (optical and electrical) of c-BN films fabricated by different synthesis techniques, with a particular emphasis on the immensely promising PLA technique. In particular, the paper focuses on the processes used to obtain phase-pure c-BN films via epitaxial growth, characterization of defects and interfaces, and control of the structural, electrical, and optical properties of these films by controlling the growth parameters, including the laser–solid interaction for the direct conversion of nanocrystalline hexagonal boron nitride (h-BN) into crystalline c-BN using the PLA technique. The latest developments in c-BN electronics are also discussed, with a focus on producing p-and n-type conductivity using different dopants to achieve dopant concentrations far beyond the retrograde thermodynamic solid solubility limits. Finally, the future prospects and possible applications in emerging areas are discussed, as well as the goals and guidelines for future research of PLA-grown c-BN films. A comprehensive overview of the properties, application, characterization, shortcomings, and future prospects of c-BN [ABSTRACT FROM AUTHOR]

The effect of the recrystallization degree on the properties of passive films formed in 0.1 M HNO3 solution for super ferritic stainless steel S44660 was examined in this study. The initial specimens, in their cold-rolled state, showed a high dislocation density, as observed through electron backscatter diffraction (EBSD) experiments. Analysis of potentiodynamic polarization (PDP) curves and electrochemical impedance spectroscopy (EIS) measurements suggested that with the increase of recrystallization degree, the corrosion current density reduced and the corrosion potential increased. As revealed by Mott–Schottky analysis, the passive film showed a dual structure of n-type and p-type semiconductors, with the carrier density of the passive film decreasing as the recrystallization degree increased. X-ray photoelectron spectroscopy (XPS) provided insights into the film composition, indicating that the Fe2O3 and Cr2O3 content, which improved the stability of the passive film, increased with the degree of recrystallization. In summary, the increase in recrystallization degree reduced the number of defects in the microstructure, thereby creating favorable conditions for the formation of highly protective passive films. The passive film formed after complete recrystallization exhibited enhanced corrosion resistance. [ABSTRACT FROM AUTHOR]

n‐type Mg3(Sb, Bi)2 has excellent room temperature thermoelectric performance, which is, however, severely restricted by the negatively charged Mg vacancies that significantly deteriorate the carrier mobility. Herein, by manipulating the threshold solubility and defect formation energy of Mn, multivalent Mn is selectively introduced that synergistically promotes the carrier conduction according to different Mg chemical potentials; In Mg‐rich areas, interstitial Mn dominates which effectively reduces the migration and accumulation of Mg vacancies, while in Mg poor areas, interstitial Mn switches to substitutional sites that directly compensate for the negative charge. All the Mn centers possess Jahn–Teller inactive positions, leading to an ultra‐stable room temperature thermoelectric performance with a leading ZT up to 0.97. This work reveals the critical effect of multivalent and multifunctional transition metal incorporation in Mg3(Sb, Bi)2‐based alloys toward high room‐temperature thermoelectric performance. [ABSTRACT FROM AUTHOR]

A chemical bath deposition (CBD) is applied to deposit n‐type iron sulfide (FeSxOy) film on fluorine (F)‐doped tin oxide (SnO2)–FTO substrate. The duration, temperature, and magnetic stirrer's speed in CBD are 3 h, 75 °C, and 100 revolutions per minute. The influence of complexing agents’ concentration (≤200 mm)–acid (tartaric and lactic) on the physicochemical properties of film is studied. All films are n‐type semiconductors with large bandgap (2.95–3.58 eV) and contain high oxygen (≈56–83%). Scanning electron microscopy image shows the 50 mm tartaric acid film has a uniform and denser surface morphology. FeSxOy film with tartaric acid has lesser goethite and hematite peaks in X‐ray diffraction than lactic acid. The FeSxOy film with 100 mm lactic acid exhibits a slightly higher transmittance at ≈350–450 nm. The FeSxOy homostructure reveals average open‐circuit voltage (Voc) = 0.45 V, short‐circuit current (Jsc) = 0.0003 mA cm−2, fill factor =38%, and efficiency (η) = 0.57%. [ABSTRACT FROM AUTHOR]

HKUST-1 MOF and HKUST-1-based compounds have been employed to develop active photocatalytic materials; however, a deep understanding of several fundamental physicochemical properties to explain the photocatalytic activity of these materials is limited. Several physicochemical properties of HKUST-1 were studied through experimental and computational approaches to determine its (photo)electrochemical (PEC) properties and applications. These properties were correlated with the structural features of the material and the photocatalytic activity towards the hydrogen evolution reaction. A meticulous characterization confirmed the synthesis of HKUST-1 using a slow evaporation methodology. XRD measurements revealed a large crystallite size (≈123 nm). Meanwhile, UV-vis spectroscopy, electrochemical measurements, and DFT calculations allowed us to identify three fundamental issues that limit the photocatalytic activity of HKUST-1: (i) a low relative permittivity of the semiconductor (εr), (ii) a wide bandgap value, and (iii) a low reduction potential for the conduction band (CB). The issues mentioned above are related to high porosity, a small conjugated system, and the presence of open metal sites in the secondary building units (SBU) that constitute the CB, respectively. Instability problems are also related to the decrement of the observed open metal sites. Regarding PEC measurements, it was determined that HKUST-1 is an n-type semiconductor suitable for photocatalytic reduction or PEC oxidation processes, however, it presents recombination issues. Determining the relative permittivity for HKUST-1 through computational tools provides an accurate methodology to calculate the density of charge carriers (ND) through the Mott–Schottky equation. The measurements and analysis presented in this work point out the main issues responsible for low photocatalytic hydrogen evolution and suggest the employment of HKUST-1 in PEC oxidation processes. [ABSTRACT FROM AUTHOR]

The backwardness of n‐type organic semiconductors still exists compared with the p‐type counterparts. Thus, the development of high‐performance n‐type organic semiconductors is of great importance for organic electronic devices and their integrated circuits. In recent years, azabenzannulated perylene diimide (PDI), as one of immense bay‐region‐annulated PDI derivatives, has drawn considerable attentions. However, the electronic mobilities of azabenzannulated PDI derivatives are barely satisfactory. In this contribution, the peripheral benzene ring in azabenzannulated PDI 2 was fused to the ortho position by intramolecular C−H arylation cyclization. This endows the resultant azabenzannulated PDI 4 a planar configuration as well as electron deficient pentagonal ring. As a result, the electronic mobility of 4 is almost two orders of magnitude higher than that of the nonfused azabenzannulated PDI 2. This work shall pave a new avenue in elevating the performance of azabenzannulated PDI in organic electronics. [ABSTRACT FROM AUTHOR]

Wide bandgap (WBG) and ultrawide bandgap (UWBG) semiconductors in n‐type metal–oxide–semiconductor (n‐MOS) integrated circuits (ICs) are increasingly being explored for their potential applications in the rapidly developing field of electronics. This review comprehensively examines the role of n‐MOS inverters underpinned by WBG and UWBG semiconductors and their application possibilities. It delves into various n‐MOS inverter topologies, including resistive, enhancement or diode‐load, depletion‐load, and pseudo‐complementary MOS inverter topologies. Each topology's operational principles, unique advantages, and potential performance are elucidated in detail. Finally, these topologies are simulated using the Advanced Design System software for a fair comparison between various topologies. The literature and simulation results show that the pseudo‐D topology has the best gain and improved noise margin. The review methodology involves an extensive exploration of WBG/UWBG n‐MOS inverters to advance the current understanding of WBG/UWBG n‐MOS‐based ICs. [ABSTRACT FROM AUTHOR]

Photocatalysis with plasmonic nanoparticles (NPs) is emerging as an attractive strategy to make and break chemical bonds. However, the fast relaxation dynamics of the photoexcited charge carriers in plasmonic NPs often result in poor yields. The separation and extraction of photoexcited hot‐charge carriers should be faster than the thermalization process to overcome the limitation of poor yield. This demands the integration of rationally chosen materials to construct hybrid plasmonic photocatalysts. In this work, the enhanced photocatalytic activity of gold nanoparticle‐titanium dioxide metal‐semiconductor heterostructure (Au‐TiO2) is used for the efficient regeneration of nicotinamide (NADH) cofactors. The modification of plasmonic AuNPs with n‐type TiO2 semiconductor enhanced the charge separation process, because of the Schottky barrier formed at the Au–TiO2 heterojunction. This led to a 12‐fold increment in the photocatalytic activity of plasmonic AuNP in regenerating NADH cofactor. Detailed mechanistic studies revealed that Au‐TiO2 hybrid photocatalyst followed a less‐explored light‐independent pathway, in comparison to the conventional light‐dependent path followed by sole AuNP photocatalyst. NADH regeneration yield reached ~70% in the light‐independent pathway, under optimized conditions. Thus, our study emphasizes the rational choice of components in hybrid nanostructures in dictating the photocatalytic activity and the underlying reaction mechanism in plasmon‐powered chemical transformations. [ABSTRACT FROM AUTHOR]

In this paper, a new 0D Ag(I)‐based coordination polymer [Ag2(dib)(H2L)2](1) is proposed as a photocatalyst for the photocatalytic degradation of nitrofurantoin (NFT) under ultraviolet irradiation. The catalytic 1 was analyzed by various methods such as PXRD, SEM, FT‐IR, TGA, UV–vis, DRS, and electrochemical tests. The experimental result shows that 1 is an n‐type semiconductor, which can effectively catalyze the photodegradation of NFT under ultraviolet irradiation. Under the optimal reaction conditions, the photodegradation rate of NFT was 97.95% within 60 min when the concentration of NFT was 30 ppm. The experiment of free radical capture shows that O2˙− is the main active substance for photodecomposition, and the possible mechanism of 1 catalytic degradation of NFT is proposed. This research will lay the foundation for Ag(I)‐based coordination polymers in the field of antibiotic photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Cu3N films are investigated utilizing direct current magnetron sputtering from the Cu target in an Ar/N2 mixed sputtering gas. X-ray diffractive analysis, Ultra-violet absorption spectroscopy, X-ray dispersive spectroscopy, atomic force microscopy, field-emission scanning electron microscopy, Hall measurements, and I–V characteristic measurements are used to investigate the properties of the films. The study findings initially obtained films with a Cu3N composition at the appropriate substrate temperature of 80 °C. When the N2:(Ar + N2) gas ratio is more than 50%, the electrical property of films switches from n-type to p-type. The film obtains the greatest crystal quality and the best p-type electric property at the N2:(Ar + N2) gas ratio of 70%, with resistivity, hole concentration, and hole mobility of 1.18 × 10–2 Ωcm, 9.8 × 1019 cm−3, and 5.4 cm2V−1 s−1, respectively. A p–n Cu3N homojunction cell has an efficiency of 0.21%. [ABSTRACT FROM AUTHOR]

One-dimensional carbon nanotubes are promising candidates for thermoelectrics because of their excellent electrical and mechanical properties. However, the large n-type power factor remains elusive in macroscopic carbon nanotubes films. Herein, we report an outstanding n-type power factor of 6.75 mW m−1 K−2 for macroscopic carbon nanotubes films with high electrical and thermal conductivity. A high-power density curl-able thermoelectric generator is fabricated with the obtained carbon nanotubes films, which exhibits a high normalized power output density of 2.75 W m−1 at a temperature difference of 85 K. The value is higher than that of previously reported flexible all-inorganic thermoelectric generators (<0.3 W m−1). An intelligent temperature controller with automated temperature-controlling ability is fabricated by assembling these thermoelectric generators, which demonstrates the potential application of the carbon nanotubes films in automated thermal management of electronic devices where requires a large thermoelectric power factor and a large thermal conductivity simultaneously. Authors obtain high n-type thermoelectric power factor in carbon nanotube films for potential application in automated thermal management of electronic devices. They fabricate a high-power density curl-able thermoelectric generator with carbon nanotubes films. [ABSTRACT FROM AUTHOR]

We present a comprehensive investigation into the potential of n-type indium-doped cadmium selenide telluride (CST:In) as a high-performance candidate for solar cell applications, without the need for resource-intensive post-growth treatments that are required for CdTe:In. We compared undoped CST and CST:In crystals under different growth conditions, analyzing their structural and electronic properties using x-ray diffraction (XRD), electron probe microanalysis (EPMA), current–voltage (IV) and Hall effect measurements, time-resolved photoluminescence (TRPL), optical transmission, and photoluminescence (PL) mapping. The results reveal that as-grown CST:In crystals achieve nearly 100% carrier activation, yielding an electron concentration of 9.5 × 1018 cm−3, mobility of 653 cm2/V·s and a 5 ns lifetime which approaches the radiative limit. Furthermore, comparison of PL maps from crystal growths having different cooling profiles suggests a strong effect of cooling rate on selenium segregation and cubic/hexagonal/polytype phase distribution. Slower cooling leads to a more homogeneous cubic structure with lower Se segregation, while a faster cooling rate results in increased Se segregation, and twin boundaries and stacking faults with polytypic and hexagonal character. [ABSTRACT FROM AUTHOR]

The evolutions of chip thermal management and micro energy harvesting put forward urgent need for micro thermoelectric devices. Nevertheless, low‐performance thermoelectric thick films as well as the complicated precision cutting process for hundred‐micron thermoelectric legs still remain the bottleneck hindering the advancement of micro thermoelectric devices. In this work, an innovative direct melt‐calendaring manufacturing technology is first proposed with specially designed and assembled equipment, that enables direct, rapid, and cost‐effective continuous manufacturing of Bi2Te3‐based films with thickness of hundred microns. Based on the strain engineering with external glass coating confinement and controlled calendaring deformation degree, enhanced thermoelectric performance has been achieved for (Bi,Sb)2Te3 thick films with highly textured nanocrystals, which can promote carrier mobility over 182.6 cm2 V−1 s−1 and bring out a record‐high zT value of 0.96 and 1.16 for n‐type and p‐type (Bi,Sb)2Te3 thick films, respectively. The nanoscale interfaces also further improve the mechanical strength with excellent elastic modules (over 42.0 GPa) and hardness (over 1.7 GPa), even superior to the commercial zone‐melting ingots and comparable to the hot‐extrusion (Bi,Sb)2Te3 alloys. This new fabrication strategy is versatile to a wide range of inorganic thermoelectric thick films, which lays a solid foundation for the development of micro thermoelectric devices. [ABSTRACT FROM AUTHOR]

Interface issues with organic semiconductors on metal oxide challenge realizing a high‐performance anti‐ambipolar transistor (AAT) with stable operation. The motivation behind this research delves into the intricate landscape of AATs, elucidating their envisioned applications and constituent materials. Central to the authors, discourse is the pivotal role that fluoropolymers assume, acting as a bridge uniting n‐type metal oxide semiconductors (n‐oxide) with p‐type organic semiconductors (p‐organic), thereby unveiling a hitherto concealed facet of transistor advancement. Adopting a spatially separating layer (SSL) between p‐ and n‐type semiconductors of AAT is unconventional, but this p‐organic/SSL/n‐oxide junction (pSn) AAT exhibits stable operation also 215 days after fabrication and minimal hysteresis, which is 13.67 times smaller than a conventional p‐organic/n‐oxide junction (pn) AAT. The effect of SSL is closely studied through comparisons of the performance of single‐type transistors, trap density, and carrier behavior, which define the order of 1/f at low‐frequency noise analysis. In addition, the contribution of SSL is confirmed via the channel formation mechanism of AAT investigated through a two‐dimensional (2D) finite‐element simulation. The operation stability of pSn AAT is evaluated through combined stress tests, long‐term stability tests, and transient response tests. This research proposes SSL as a new design parameter to improve the AAT. [ABSTRACT FROM AUTHOR]

Thermoelectric cooling has gained much attention due to its significant application in 5G communication chip cooling. Enhancing the performance of thermoelectric cooling devices is an imminent and pressing concern. Applying the same material for both n‐type and p‐type components can promote the compatibility of thermoelectric cooling module due to their similar mechanical properties. This work focuses on the development of thermoelectric cooling module based on n‐type and p‐type PbTe ingots. The high ZT values near room temperature are achieved through fabricating PbTe ingots. This approach substantially enhances the carrier mobility by minimizing charge carrier scattering at grain boundaries compared to polycrystals. These optimized ingots are then utilized to construct a thermoelectric cooling device consisting of seven pairs of thermoelectric couples, which achieves a maximum cooling temperature difference of ≈14 K at room temperature and ≈28 K at 350 K. This study offers fresh insights into the development of thermoelectric cooling module using PbTe‐based materials. [ABSTRACT FROM AUTHOR]

For N‐type tunnel‐oxide‐passivated‐contact silicon solar cells, optimal Ag/Al–Si contact interface is crucial to improve the efficiency. However, the specific roles of Ag and Al at the interface have not been clearly elucidated. Hence, this work delves into the sintering process of Ag/Al paste and examines the impact of the Ag/Al–Si interface structure on contact quality. By incorporating TeO2 into PbO‐based Ag/Al paste, the Ag/Al–Si interface structure can be modulated. It can be found that TeO2 accelerates the sintering of Ag powder and increases Ag colloids within glass layer, while it simultaneously impedes the diffusion of molten Al. It leads to a reduced Al content near the Ag/Al–Si interface and a shorter diffusion distance of Al into Si. Notably, it can be demonstrated that the diffusion of Al in Si layer is more effective to reduce the contact resistance than the precipitation of Ag colloids. Therefore, the PbO‐based Ag/Al paste, which favors Al diffusion, leads to solar cells with lower contact resistance and series resistance, higher fill factor, and superior photoelectric conversion efficiency. In brief, this work is significant for optimizing metallization of silicon solar cells and other semiconductor devices. [ABSTRACT FROM AUTHOR]

Ligand‐protected heterometallic nanoclusters in contrast to homo‐metal counterparts show more broad applications due to the synergistic effect of hetero‐metals but their controllable syntheses remain a challenge. Among heterometallic nanoclusters, monovalent Ag‐Cu compounds are rarely explored due to much difference of Ag(I) and Cu(I) such as atom radius, coordination habits, and redox potential. Encouraged by copper‐catalyzed alkyne‐azide cycloaddition (CuAAC) reaction, comproportionation reaction of Cu(II)X2 and Cu(0) in the presence of (PhC≡CAg)n complex and molybdate generated a core‐shell peanut‐shaped 66‐nuclear Ag(I)‐Cu(I) heterometallic nanocluster, [(Mo4O16)2@Cu12Ag54(PhC≡C)50] (referred to as Ag54Cu12). The structure and composition of Ag‐Cu heterometallic nanocluster are fully characterized. X‐ray single crystal diffraction reveals that Ag54Cu12 has a peanut‐shaped silver(I)/copper(I) heterometallic nanocage protected by fifty phenylacetylene ligands in µ3–modes and encapsulated two mutually twisted tetramolybdates. Heterometallic nanocage contains a 54‐Ag‐atom outer ellipsoid silver cage decorated by 12 copper inside wall. Nanosized Ag54Cu12 is a n‐type narrow‐band‐gap semiconductor with a good photocurrent response. Preliminary experiments demonstrates that Ag54Cu12 itself and activated carbon supported Ag54Cu12/C are effective catalysts for 1,3‐dipole cycloaddition between alkynes and azides at ambient conditions. The work provides not only a new synthetic route toward Ag(I)‐Cu(I) nanoclusters but also an important heterometallic intermediate in CuAAC catalytic reaction. [ABSTRACT FROM AUTHOR]

Visible-light-driven Bi2WO6/BiVO4 (BWO/BVO) heterostructures were obtained by joining BWO and BVO n-type semiconductors. A novel and green metathesis-assisted molten salt route was applied to synthesize BWO/BVO. This route is straightforward, high-yield, intermediate temperature, and was successful for obtaining BWO/BVO heterostructures with several ratios (1:1, 1:2, 2:1 w/w). Besides, the 1BWO/1BVO was decorated with Ag nanoparticles (Ag-NPs, 6 wt.%) and graphene (G, 3 wt.%), applying simple and environmentally responsible procedures. The heterostructures were characterized by XRD, Raman, UV–Vis DRS, TEM/HRTEM, PL, and Zeta potential techniques. Ag-NPs and G effectively boosted the photocatalytic activity of 1BWO/1BVO for degrading tetracycline (TC) and rhodamine B (RhB) pollutants. A lab-made 19-W blue LED photoreactor was designed, constructed, and operated to induce the photoactivity of BWO/BVO heterostructures. The low-rated power consumption of the photoreactor (0.01–0.04 kWh) vs. the percent degradation of TC or RhB (%XTC = 73, %XRhB = 100%) is one of the outstanding features of this study. Besides, scavenger tests determined that holes and superoxides are the main oxidative species that produced TC and RhB oxidation. Ag/1BWO/1BVO exhibited high stability in reuse photocatalytic cycles. [ABSTRACT FROM AUTHOR]

High-performance photovoltaic devices require active photoanodes with superior optoelectric properties. In this study, we synthesized neodymium ruthenate, Nd2Ru2O7 (NRO), and gadolinium ruthenate pyrochlore oxides, Gd2Ru2O7 (GRO), via the solid-state reaction technique, showcasing their potential as promising candidates for photoanode absorbers to enhance the efficiency of dye-sensitized solar cells. A structural analysis revealed predominantly cubic symmetry phases for both materials within the Fd-3m space group, along with residual orthorhombic symmetry phases (Nd3RuO7 and Gd3RuO7, respectively) refined in the Pnma space group. Raman spectroscopy further confirmed these phases, identifying distinct active modes of vibration in the predominant pyrochlore oxides. Additionally, a scanning electron microscopy (SEM) analysis coupled with energy-dispersive X-ray spectroscopy (EDX) elucidated the morphology and chemical composition of the compounds. The average grain size was determined to be approximately 0.5 µm for GRO and 1 µm for NRO. Electrical characterization via I-V measurements revealed that these pyrochlore oxides exhibit n-type semiconductor behavior, with conductivity estimated at 1.5 (Ohm·cm)−1 for GRO and 4.5 (Ohm·cm)−1 for NRO. Collectively, these findings position these metallic oxides as promising absorber materials for solar panels. [ABSTRACT FROM AUTHOR]

In this research, the photocatalytic degradation of methylene blue was investigated using synthesized PdO/CoS nanocomposite under visible light irradiation. The structural and morphological properties were determined using X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area analysis, Mott–Schottky analysis, and transmission electron microscopy (TEM). The Mott–Schottky analysis confirmed the formation of a p-n heterojunction, and the flat band potential values for the n-type and p-type semiconductors were found to be − 1 and 1.3, respectively. The bandgap of the composite was determined to be 3 eV using Diffuse Reflectance Spectroscopy (DRS). When 0.1 g of the synthesized composite was used for 90 min, it successfully degraded 91% of methylene blue with an initial concentration of 10 ppm. In the Design of Experiments (DOE) approach, the optimum conditions for this research were found to be a catalyst mass of 0.06 g, an initial dye concentration of 8 ppm, and 2% palladium doping at pH 10, resulting in a 92.38% degradation efficiency in 110 min. To model the degradation of methylene blue using the synthesized composite, the Fritz–Schlunder and Koble–Corrigan models achieved the highest correlation coefficients (0.995 and 0.992, respectively) and the lowest error functions (0.024, 0.0008) and (0.032, 0.002), respectively. Additionally, the Langmuir–Hinshelwood and Intra-particle diffusion control kinetic models showed the highest correlation coefficient (98%). In summary, the study demonstrated that the PdO/CoS composite exhibited excellent photocatalytic activity for methylene blue degradation, and the optimized conditions resulted in high degradation efficiency. The proposed kinetic models provided valuable insights into the degradation mechanism of methylene blue using the synthesized composite. [ABSTRACT FROM AUTHOR]

Combining DFT-based calculations with Boltzman transport formalism, thermoelectric transport properties of semiconducting two-dimensional SiC-CrS2 and SiC-CrSe2 van der Waal heterostructures are investigated in unstrained and strained conditions. We computed electronic, optical and thermoelectric properties of these heterostructures. We find that these heterostructures are direct band semiconductors having type-II band alignment in unstrained conditions. The transition from the direct to the indirect band is observed in SiC-CrSe2 with compressional strain. Switching from type-II to type-I band alignment is also observed under strained conditions in SiC-CrS2. For thermoelectric properties, we have calculated the Seebeck coefficient, electrical conductivity per relaxation time and power factor at 300 K. Analysis of the power factor revealed a preference for n-type doping under zero strain conditions, whereas changes in PF values induced by strain underscored the potential for tuning the thermoelectric performance of these heterostructures. [ABSTRACT FROM AUTHOR]

The current investigation reports the tuning of p-type semiconduction in nanocrystalline BiSbTe1. 5Se1.5 high entropy alloy (HEA) by Ag doping (0.3–0.9 at%) processed through mechanical alloying (MA) and spark plasma sintering (SPS). The entropy engineering and nanostructuring phenomena synergistically lower the thermal conductivity (K) below 1 W/mk in all samples. The superior ZT value of 0.45 is achieved in p-type BiSbTe1.5Se doped with 0.6 at% Ag doping, comparable with its n-type BiSbTe1.5Se1.5 possessing ZT of 0.43 at 523 K. The consistency in material chemistry and identical temperature dependence of ZT in both p-type and n-type materials of the current investigation provide promising perspectives for developing low-loss thermoelectric generators. [ABSTRACT FROM AUTHOR]

A simple synthetic route to poorly available polycyclic systems with a [1,2,5]oxadiazolo-[3,4-b]quinoxaline backbone has been developed, which is based on the sequence of nucleophilic aromatic substitution of hydrogen and the Scholl cross-coupling. According to the data from electrochemical and photophysical measurements, the synthesized compounds can be potentially considered as the narrow-gap (from 1.97 to 2.34 eV) n-type organic semiconductors, the energy levels of which are comparable to those of top commercially available electronic semiconductors. [ABSTRACT FROM AUTHOR]

Field effect transistors based on few-layered van der Waals transition metal halide (TMH) Nb3Cl8 are studied in this work. Few-layered Nb3Cl8 exhibits typical N-type semiconducting behavior controlled by a Si gate, with the electrical signal enhancing as the thickness increases from 4.21 nm to 16.7 nm. Moreover, we find that the tunability of few-layered Nb3Cl8 FETs' electrical transport properties can be significantly augmented through the use of an ionic liquid gate (or electrical double layer, EDL). This enhancement leads to a substantial increase in the on–off ratio by approximately a factor of 10 2 , with the transfer curve modulated into a bipolar fashion. The emergence of such bipolar tunable characteristics in Nb3Cl8 FETs serves to enrich the electronic properties within the transition metal halide family, positioning Nb3Cl8 as a promising candidate for diverse applications spanning transistors, logic circuits, neuromorphic computing and spintronics. [ABSTRACT FROM AUTHOR]

Diluted magnetic semiconductors have become a research area in the past few years due to the importance of new technology, spintronics devices, and green technology to withstand rising global temperatures. Both n‐type and p‐type diluted magnetic semiconductors are used in pairs for perfect performance, especially for p‐n junction diodes, the p‐d Zener model, GMR, and TMR spintronics devices. The main challenge for some researchers is to find a ferromagnetic diluted magnetic semiconductor with a Curie temperature greater than room temperature for both n‐type and p‐type ferromagnetic diluted semiconductors, but this study has solved this problem. In the present study, the ferromagnetic properties of an n‐type gallium iron antimonide diluted semiconductor have been studied using the Hamiltonian model without applying an external magnetic field, electric field, or chemical potential. We have formulated a Hamiltonian model in the system, considering the application of the green formalism function and the transformation of Holstein–Primakaff. The Curie temperature, dispersion, number of magnons, reduced magnetization, and specific heat capacity of ferromagnetic magnons of the n‐type (Ga, Fe)Sb formula are formulated. The Curie temperature versus concentration graph is plotted, and the specific heat capacity and magnetization versus temperature graphs are plotted. In this study, a surprising situation is that the Curie temperature of Ga0.8Fe0.2Sb$G{\mathrm{a}}_{0.8}F{e}_{0.2}\textit{Sb}$ n‐type diluted magnetic semiconductor is investigated above room temperature, which is 330.4 K. The ferromagnetic properties of Ga0.8Fe0.2Sb$G{\mathrm{a}}_{0.8}F{e}_{0.2}\textit{Sb}$ appear up to 330.4 K, which is able to play a major role in spintronic and next‐generation green nanotechnology devices. [ABSTRACT FROM AUTHOR]

Silicon nitride (Si3N4) possesses excellent mechanical properties and high thermal conductivity, which is an important feature in many applications. However, achieving the theoretically high thermal conductivity of Si3N4 in practice is challenging. In this study, we adopted a first-principles calculation method to assess the effects of doping β-Si3N4 and γ-Si3N4 with carbon and oxygen atoms. Applying geometric structure optimization combined with calculation of the electronic phonon properties generated a stable doped structure. The results revealed that carbon and oxygen doping have little effect on the Si3N4 unit cell size, but that oxygen doping increases the unit cell volume. Energy band structure and state density calculation results showed that carbon doping reduces the nitride band gap width, whereas oxygen doping results in an n-type Si3N4 semiconductor. The findings from this study are significant in establishing a basis for targeted increase of the thermal conductivity of Si3N4. [ABSTRACT FROM AUTHOR]

A simple synthetic route to poorly available polycyclic systems with a [1,2,5]oxadiazolo-[3,4-b]quinoxaline backbone has been developed, which is based on the sequence of nucleophilic aromatic substitution of hydrogen and the Scholl cross-coupling. According to the data from electrochemical and photophysical measurements, the synthesized compounds can be potentially considered as the narrow-gap (from 1.97 to 2.34 eV) n-type organic semiconductors, the energy levels of which are comparable to those of top commercially available electronic semiconductors. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have gained much attention in recent years because of their improved energy conversion efficiency, simple fabrication process, low processing temperature, flexibility, light weight, and low cost of constituent materials when compared with their counterpart silicon based solar cells. Besides, stability and toxicity of PSCs and low power conversion efficiency have been an obstacle towards commercialization of PSCs which has attracted intense research attention. In this research paper, a Glass/Cu2O/CH3NH3SnI3/ZnO/Al inverted device structure which is made of cheap inorganic materials, n-type transparent conducting oxide (TCO)-free, stable, photoexcited toxic-free perovskite have been carefully designed, simulated and optimized using a one-dimensional solar cell capacitance simulator (SCAPS-1D) software. The effects of layers' thickness, perovskite's doping concentration and back contact electrodes have been investigated, and the optimized structure produced an open circuit voltage (Voc) of 1.0867 V, short circuit current density (JSC) of 33.4942 mA/cm2, fill factor (FF) of 82.88% and power conversion efficiency (PCE) of 30.17%. This paper presents a model that is first of its kind where the highest PCE performance and eco-friendly n-type TCO-free inverted CH3NH3SnI3 based perovskite solar cell is achieved using all-inorganic transport materials. [ABSTRACT FROM AUTHOR]

Perylenetetracarboxylic diimide (PTCDI) is an n-type organic semiconductor molecule that has been widely utilized in numerous applications such as photocatalysis and field-effect transistors. Polarizability and dipole moment, which are inherent properties of molecules, are important parameters that determine their responses to external electric and optical fields, physical properties, and reactivity. These parameters are fundamentally important for the design of innovative materials. In this study, the effects of external electric fields on absorption and fluorescence spectra were investigated to obtain the PTCDI parameters. The PTCDI substituted by an octyl group (N,N′-Dioctyl-3,4,9,10-perylenedicarboximide) dispersed in a polymethyl methacrylate (PMMA) matrix was studied in this work. The features of vibronic progression in the absorption spectrum were analogous to those observed in solution. The red shift of the absorption band caused by the Stark effect was mainly observed in the presence of an external electric field. Changes in parameters such as the dipole moment and polarizability between the ground and the Franck–Condon excited states of the PTCDI monomer were determined. The fluorescence spectrum shows a contribution from a broad fluorescence band at wavelengths longer than the monomer fluorescence band. This broad fluorescence is ascribed to the excimer-like fluorescence of PTCDI. The effects of the electric field on the fluorescence spectrum, known as the Stark fluorescence or electrofluorescence spectrum, were measured. Fluorescence quenching is observed in the presence of an external electric field. The change in the polarizability of the monomer fluorescence band is in good agreement with that of the electroabsorption spectrum. A larger change in the polarizability was observed for the excimer-like fluorescence band than that for the monomer band. This result is consistent with exciton delocalization between PTCDI molecules in the excimer-like state. [ABSTRACT FROM AUTHOR]